{"id":22992,"date":"2020-04-18T16:47:15","date_gmt":"2020-04-18T14:47:15","guid":{"rendered":"http:\/\/www.leblogdescoutheillas.com\/?p=22992"},"modified":"2020-04-19T08:12:44","modified_gmt":"2020-04-19T06:12:44","slug":"journal-de-campagne-34","status":"publish","type":"post","link":"https:\/\/www.leblogdescoutheillas.com\/?p=22992","title":{"rendered":"Journal de Campagne (34)"},"content":{"rendered":"

Journal de Campagne (34)<\/strong>
\nSamedi 18 avril 2020 \u2013 16h47<\/em><\/p>\n

D\u00e9monstration<\/u><\/p>\n

Soient\u00a0:
\n(P) l\u2019ensemble de la population fran\u00e7aise, et
\n(V) inclus dans (P), le sous-ensemble des \u00ab\u00a0Vieux\u00a0\u00bb, et
\n(NV) compl\u00e9mentaire de (V) dans (P), le sous-ensemble des \u00ab\u00a0Non-vieux\u00a0\u00bb<\/p>\n

Soient n(P), n(V) et n(NV) le nombre d\u2019\u00e9l\u00e9ments respectivement contenus dans (P), (V) et (NV)<\/p>\n

On donne\u00a0 \u00a0 \u00a0 \u00a0 n(P) = 65.106<\/sup>
\net\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 n(V) = n(P). 10-1\u00a0\u00a0<\/sup> = 6,5.106<\/sup><\/p>\n

(P) = (V) + (NV) \u00a0=> \u00a0n(P) = n(V) + n(NV)\u00a0 => n(NV) = n(P) \u2013 n(V) = \u00a058,5.106<\/sup><\/p>\n

On rappelle que le COVID-19 se propage par mise en pr\u00e9sence d\u2019au moins deux \u00e9l\u00e9ments de (P) quel que soit leur sous-groupe (V) ou (NV) et on admettra par hypoth\u00e8se que les cons\u00e9quences du COVID-19 sont supportables pour les \u00e9l\u00e9ments de l\u2019ensemble (NV), et contrariantes pour les \u00e9l\u00e9ments de (V). \u00c9galement par hypoth\u00e8se, on admettra que l\u2019objectif de l\u2019exercice est d\u2019\u00e9viter les contrari\u00e9t\u00e9s aux \u00e9l\u00e9ments de (V).<\/p>\n

On sait par ailleurs qu\u2019en l\u2019absence d\u2019un vaccin, la propagation du COVID-19 entre \u00e9l\u00e9ments de (P) ne s\u2019arr\u00eatera que lorsque que 60% de ses \u00e9l\u00e9ments se seront naturellement immunis\u00e9s apr\u00e8s contagion.<\/p>\n

En attendant que ce seuil soit atteint, et pour remplir l\u2019objectif admis plus haut, il conviendra donc d\u2019isoler (ou confiner) les \u00e9l\u00e9ments de (V) jusqu\u2019\u00e0 l\u2019arr\u00eat de la contagion, c\u2019est \u00e0 dire jusqu\u2019\u00e0 ce que (n(P) x 60%) \u00e9l\u00e9ments appartenant \u00e0 (P) aient \u00e9t\u00e9 immunis\u00e9s, c\u2019est-\u00e0-dire pr\u00e9alablement contamin\u00e9s.<\/p>\n

Mais, par hypoth\u00e8se, les \u00e9l\u00e9ments de (V) \u00e9tant \u00e0 l\u2019isolement, les \u00e9l\u00e9ments \u00e0 immuniser devront se trouver uniquement dans l\u2019ensemble (NV).<\/p>\n

Pour satisfaire \u00e0 la condition portant sur le nombre minimal de contamin\u00e9s-immunis\u00e9s, il faudra que le nombre de contamin\u00e9s dans (NV) soit bien s\u00fbr \u00e9gal\u00a0\u00e0\u00a0: n(P) x 60%, d\u2019o\u00f9 la proportion Q, sup\u00e9rieure \u00e0 60%, n\u00e9cessaire de contamin\u00e9s dans (NV), avec\u00a0:<\/p>\n

Q = (n(P) x 60%) \/ n(NV) = (n(P) x 60%) \/ (n(P) x 90%) = 60 \/ 90 = 2\/3<\/p>\n

On voit donc qu\u2019il faudra attendre que les 2\/3 des Non-vieux aient \u00e9t\u00e9 contamin\u00e9s pour pouvoir d\u00e9sisoler les Vieux d\u00e9sol\u00e9s. Si on d\u00e9signe par (NV+) le sous ensemble des \u00e9l\u00e9ments de (NV) contamin\u00e9s, on a\u00a0:<\/p>\n

n(NV+) = n(NV) x (2\/3) = 58,6.106<\/sup> x 0,6666667 = 39,67.106 <\/sup>= 39.670.000 \u00e9l\u00e9ments<\/p>\n

Dans un prochain exercice, nous calculerons le temps qui sera n\u00e9cessaire pour atteindre ce seuil de 39, 67 millions de contamin\u00e9s-immunis\u00e9s. Ce qu\u2019on peut dire d\u2019ores et d\u00e9j\u00e0 en premi\u00e8re approximation, c\u2019est que ce n\u2019est pas demain la veille.<\/p>\n

Toutes r\u00e9flexions faites, et pour ne pas d\u00e9sesp\u00e9rer Billancourt, peut-\u00eatre vaudrait-il mieux ne pas faire ce calcul.<\/p>\n","protected":false},"excerpt":{"rendered":"

Journal de Campagne (34) Samedi 18 avril 2020 \u2013 16h47 D\u00e9monstration Soient\u00a0: (P) l\u2019ensemble de la population fran\u00e7aise, et (V) inclus dans (P), le sous-ensemble des \u00ab\u00a0Vieux\u00a0\u00bb, et (NV) compl\u00e9mentaire de (V) dans (P), le sous-ensemble des \u00ab\u00a0Non-vieux\u00a0\u00bb Soient n(P), n(V) et n(NV) le nombre d\u2019\u00e9l\u00e9ments respectivement contenus dans (P), (V) et (NV) On donne\u00a0 … Continuer la lecture de Journal de Campagne (34)<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mo_disable_npp":"","_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[6],"tags":[1560,21],"class_list":["post-22992","post","type-post","status-publish","format-standard","hentry","category-news","tag-covid-19","tag-philippe"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=\/wp\/v2\/posts\/22992","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=22992"}],"version-history":[{"count":0,"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=\/wp\/v2\/posts\/22992\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=22992"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=22992"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.leblogdescoutheillas.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=22992"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}